The present invention relates to a method of producing imitated panelled doors and similar panelling elements, which appear with a frame portion and a front surface plane, and one or more partial area portions with recessed surface planes. In the old prior art such panelling element consisted of a frame of joined board portions forming one or more openings in which were inserted infilling panels, the edge portions of these as well as optionally the adjacent edges of the frame board portions being profiled for forming characteristic subframe patterns. The other sides of the infilling panels may well be flush with the outer sides of the frame portion, but in the transition areas along the edges of the panels the outer side will be recessed compared to the plane of the outer side of the frame portion.
In recent times many attempts have been made to produce such doors, furniture doors, or panelled elements with such as appearance, but by using a modernized technique whereby e.g. the frame boards are replaced by a continuous body of chipboard or similar materials. It has even been proposed that both the frame and the panel portions can be glued as separate covering elements onto a through-going base plate member. Truly it is hereby possible to provide imitated panelled doors or panel elements substantially cheaper than by the original method, but still substantial production costs have been involved relative to the modern alternative which consists of the so-called smooth doors. However, the decorative effect of a "panelled door" is so pronounced that it justifies a somewhat higher production price than for a simple smooth door.
It is the purpose of the invention to provide a method by which a door or panel element can be produced as an imitated element of the panelled type in a very inexpensive manner.
The invention is based on the consideration that the infilling panels or at least the characteristic border portions between these and the surrounding frame portion may very well be produced by a simple die pressing of an originally planar plate member when this is adapted to resist the die pressing without the occurring of visually unacceptable deformations in the surface of the plate manner. On the other hand, this condition is highly essential in practice, and the problem is that an acceptable surface made from either a wooden veneer or paper suitable for painting is difficult to shape by die pressing. It is possible that the very idea of a pattern embossing is not new, as e.g. a chip board is locally compressible, but prior attempts in this direction have not lead to practically usable results.
By the invention a method is developed by which the panelling element is constructed in a manner known per se by covering a frame structure with a relatively thin cover plate, but whereby it has been found possible to die press such a cover plate, which is specially produced for the purpose for obtaining an outer surface appearance which perfectly corresponds to the said panelling pattern. It is hereby essential that the thin plate member can be die pressed while being coated by veneer or paper and that the plate therefore, may be a wood-like character so that it does not later show warping tendencies.
In accordance with the present invention, a method of producing door or other panel elements having a relief surface is provided by a combination of construction the elements as a frame work which is provided with wood-like thin covering plates with the covering plates being utilized with an associated paper or veneer coatings which have been subjected to a previous die pressing for forming a relief surface.
However, it has been found that by using already known thin plate materials it is very difficult to obtain satisfying results, and on this background the invention also provides for a new plate material, adapted to the purpose or, more correctly, a method of producing such covering plate members based on such a pre-fabricated plate material.
In order to produce the above described plate covering members based on a prefabricated plate material, in accordance with advantageous features of the present inventions, a prefabricated thin leather-like plate member is coated with a paper or veneer, with the plate member including an only slightly pressed wood fiber or wood chip mass with a content of only partially activated heat-setting binding agent, whereafter, the thus coated plate member is subjected to a non-abrupt pressing between fully covering die pressing plates embodied with a desired matrix-patrix pattern, and with heat being supplied to the plate member during the pressing in such a manner, that the binding agent in the plate member as well as in the binding layer for the paper, a veneer coating is brought to a final setting subsequent to the establishing of a final pressing pressure, by which the relief pressing is completed and the plate member generally has been substantially compacted.
By virtue of the above noted features of the present invention, a plate material having a leather-like character is practically completely unusable until it is finished by the pressing and heating process. On the other hand, the plate material is willingly deformable by the die pressing because of the built-in binding agent is not finally activated until the pressing operating is finished, but nevertheless in direct connection herewith.
It has been found that by using a veneer coating on such a plate material it is obtainable that also the veneer is deformable for forming the desired relief pattern without cracking, which obviously is a practical prerequisite for the practical utility of the invention. It is hereby necessary that the veneer be subject to a steaming immediately before the pressing so as to be suitably deformable, and it is even a requirement that the veneer is fastened to the plate member by means of a glue, which just as the binding agent in the plate member, is not finally activated until a relatively high final temperature is reached after the pressing process has been finished.
In the following the invention is described in more detail with reference to the drawing.